1. Field of the Invention
The present invention relates to power generation systems for marine vessels, and more specifically, to a closed-loop power and propulsion generation system for an underwater vessel combining a Pulse Detonation Engine with a regenerative fuel cell.
2. Prior Art
Vehicles that operate underwater are useful for performing tasks below the sea surface in such fields as deep-water salvage operations, navy and marine operations, underwater telecommunications, offshore petroleum and mining, and oceanographic research. Many of these applications are completed by small-scale underwater vehicles that can be either manned or unmanned (remotely operated). These unmanned vehicles are commonly known as Unmanned Underwater Vehicles (UUVs).
Generally, these small-scale underwater vessels have used conventional power systems. These traditional power/propulsion generation systems for submersible vessels have relied on stored electrical power, which has limited capacities for both duration and output power.
Prototype closed-loop systems for power generation use metal/water reactions in combination with a turbine to generate power. However, these metal reactions can produce ceramic particles that can damage the turbine. Other conventional power systems run an open cycle that consumes some type of fuel and the reaction products are expelled from the vessel.
The term closed loop cycle implies that none of the working fluid enters or leaves the power system while in operation. In contrast open-loop combustion systems, such as an aircraft or automotive engines, will eject or exhaust the products of the reaction used to generate power. In the case of an open system such as a missile or torpedo, ejecting mass can be used to generate thrust and propel the vessel. Vessels operating underwater that eject or exhaust mass tend to rise as they become more buoyant. To compensate, a series of onboard tanks can be filled with an amount of seawater equal to the ejected mass. However, this adds additional mechanical complexity and the potential for leaks into to the system. Further, by expelling this mass from the vessel, the vessel becomes more buoyant and tends to rise, thus making it more likely that the vehicle will be spotted or detected. This is a problem for vehicles involved in covert operations.